Crunch Time Of The NFL Season Is Right Now

In the NFL, every single game is important. Each one represents more than 6 percent of a team’s season, and one win is often the difference between making the playoffs and not, between getting a bye and playing on wild-card weekend, or between playing at home and playing on the road. But even within the every-game-matters paradigm, the first weeks of the NFL season are special.

For us fans, early-season games set the agenda. They reveal surprises, like the 1999 Rams, who — starting an Arena league quarterback and coming off a four-win season — won their first three games with a combined score of 100-27 (including a 35-7 romp over the Atlanta Falcons). It would be weeks before people really started taking the team seriously, but if the Rams had started 0-3, they could have been safely written off. Early-season games also reveal busts, like the 1999 Atlanta Falcons, who — coming off a 14-2 season — lost their first three games by a combined score of 76-28.

In other words, these games are doubly important because they reveal both who won and who is likely to win going forward. This new information can supplement — and often supercede — a whole offseason of analysis. Yes, we have considered opinions about who’s strong and who isn’t, who did well in free agency or poorly in the draft, but outside of a small number of sure things, predicting which teams will rise or fall from year to year can be nigh impossible. Of course, we do our best.

But for the moment, let’s simplify and pretend we don’t know anything except the results right in front of us. How much is a win worth?

Late in the season, a win is worth close to face value. Each win is worth 0.5 wins above random expectation. For example, if your team is 7-7 going into the last two weeks, you’re expected to win 8 games. If you win in Week 15, you’ll be expected win 8.5, and if you lose, you’ll be expected to win 7.5.

But in the beginning of the season, wins give you one mark in the win column, while also indicating that you’re more likely than average to win going forward. To see this, let’s start with the expected fortune of any generic team with any given record. In the chart below, match up wins and losses along the axes to find the average number of wins that teams with that record have finished with since 1995:

(Incidentally, I keep a copy of this chart on my desk for quick reference, so every time a commentator says something like a 6-2 team is “on pace” to win 12 games, I can say, “Nuh-uh, they’re on pace to win 10.8.”)

Using the above chart, we can easily compare wins and losses for a given record and see which games convey the most about a team’s eventual win tally. You’ll never guess:

Since 1995, teams who win their opening game have averaged around 9.1 wins, while teams losing their opener average 6.9. So the information a win conveys makes it worth more than double its face value.

If you combine how much wins and losses tell us about every team, Week 1 is the most informative of the season, followed closely by Week 2, then big dropoffs in Weeks 3 and 4. While only 16 games are played in Week 1, we get nearly 70 wins and losses worth of information out of them:

Now, one win being the equivalent of two wins may not sound like much, but again, one win in the NFL can make a huge difference. Thus, unsurprisingly, early-season results have serious playoff implications:

The first two weeks of the season alone mark the difference between having a 61 percent chance of making the playoffs (for a 2-0 squad) and a 10 percent chance (for 0-2).

Indeed, early-season wins are so important that these games are nearly comparable in leverage to late-season games by playoff contenders:

And when you consider that every team in the league starts and 0-0 before Week 1 and enters Week 2 at 1-0 or 0-1, but only a few teams will be sitting at 9-6 in Week 17, the changes to teams’ playoff fates that take place in these first few weeks really start adding up.

For example, teams that win their opening game have made the playoffs 51 percent of the time, while teams who lose their first game have made it only 25 percent of the time. That 26 percent difference isn’t quite as high as the difference for a team that’s 7-6 (for whom each game carries a 29 percent difference), but on the other hand, every single team goes through that 25 percent difference-maker in Week 1, while relatively few will see that 29 percent game in Week 16.

If you combine how much we learn about playoff chances from week to week (as we did above for wins), you find that the first two weeks are by far the most significant of the regular season:

Each of the first two weeks tells us roughly as much about who will or won’t make the playoffs as four win-or-go-home games, which would decide eight teams’ fates. So it’s almost as if the season starts off with two rounds of playoffs — except that all the excitement is spread thin across the entire league.

Now, I know you’re a smart readership, so you’re probably thinking this is all just a bit too clever, because we have reams of knowledge about these teams already, so to some extent this “information” value is going to reflect stuff that we already know.

So give yourself a pat on the back, you’re right. But you’re also pretty much wrong. Much of what you think you know, you don’t know. And much of what you know is just a different baseline. Even for very strong and very weak teams (such as those with 12+ wins or losses the year before), the outsized leverage of first weeks of the season has been borne out.

When it comes to the NFL, there isn’t much signal and there’s a ton of noise (hi, boss!). But while individual wins and losses in September may not seem like the clearest signals you’ll ever hear, they’re deceptively strong, and they’re coming at you from 32 directions. So listen carefully.

Benjamin Morris researches and writes about sports and other topics for FiveThirtyEight. @skepticalsports